Safety for firearm sear



March 1, 1960 F. c. SCRIPTER 2,926,447

SAFETY FOR FIREARM SEAR Filed April 28, 1958 /3 fig-l- INVENT OR. /Z4/m C foe/F796 United States Patent fi" 2,926,447 Patented Mar. 1, 1960 ICC SAFETY FOR FIREARM SEAR Frank C. Scripter, Laingshurg, Mich.

Application April 28, 1958, Serial No. 731,289 4 Claims. (Cl. 42--70) The present invention comprises a novel safety mechanism for firearms.

More particularly the safety device comprising the present invention is a cross bolt type of safety which selectively operates transversely of the bolt axls to block the sear of the arm. Where it may be applied to shotguns and the like the action is transverse of the bore axis and through the trigger and receiver group.

Still more particularly the actuation of the present invention is transverse with respect to the bolt and is positioned preferably in the rear enlarged portion of the trigger housing where it is readily accessible for engagement or release at the option of the gunner.

While bolt action rifles are simple in construction and ruggedly serviceable for military and sporting use, they have had one major drawback. The safety has normally been directly associated with the bolt. Where military rifles are concerned the bolts have almost universally included a rotating tab-like lug extending rearwardly from the bolt which is rotated to lock and unlock the bolt at the desire of the rifleman. While these locks are positive and substantially foolproof they are cumbersome, interfere with scope sight mountings, and result in considerable confusion to a sportsman in use. Rifies having the characteristic Mauser bolt action such as the Mannlicher- Schoenauer, Springfied, Mauser, Enfield, and Arisaka, for example, are highly desirable as conversion pieces from military to sporting usage. In this conversion the gunsmith modifies the length of barrel, bolt details, and most certainly the stock having the aim of lightening the military piece and making it very adaptable to sporting usage. It is desirable to delete the military safety for purposes of making the safety more readily operable by the sportsman. It is also desirable to remove extraneous protuberances from the bolt so as to free the area rearwardly of the bolt for sport and scope type sights. With the deletion of the military safety the gunsmith is forced to adopt a new type of safety for the firearm. The safeties devised by gunsmiths have been found generally unsatisfactory in that they were unhandily located, were impositive in action, were easily dislodged from safe position, or required extensive inletting of stock and receiver elements. Three types of safety are generally known by reason of their action, bolt twist, being a modification of the military lock acting on the cocking action of the bolt or firing pin but cut down to minimize bulk and interference; trigger block," being a selectively locatable bar preventing rearward movement of the trigger; and sear block, normally imposing an obstacle in the path of the falling sear. The present invention comprises a safety of the latter general category. So far as it is presently known devices in this category have rarely been applied to bolt action arms, their usage having been limited to modifying the sear movement from automatic to semi-automatic positioning in military automatic and semi-automatic arms.

Accordingly, it is one of the objects of the present invention to provide a simple sear block which cannot be dislodged from selected lock positioning by chance axial shock.

It is another object of the present invention to provide a safety mechanism requiring simple inletting operation at points through the trigger housing or guard so as not to weaken any shock loaded member in the receiver group.

Another object is to provide an axially movable and reciprocable plunger unit which is located so as not to require any inletting through the stock of the firearm.

Still another object is to provide a safety which is selectively operable from the rear of the trigger guard or housing without interfering with the trigger grouping.

Other objects including the positive blocking of the scar, and the simplicity of the mechanism will become increasingly apparent to those skilled in the art as the description proceeds.

It will also be readily apparent that the safety of the present invention is easily used in making military to sporting conversions and can be economically supplied to gunsmiths for simple installation.

In original firearm equipment the safety of the present invention adapts itself nicely to controlled mass production Without sacrifice of quality and performance.

in the drawings:

Figure 1 is a side elevation view of a bolt action Mauser type rifle showing the positioning of one button end of the safety device and indicating the safe and fire positions of the sear block.

Figure 2 is a top plan view of the rifle shown in Figure 1, with the safety device transversely extending with respect to the bolt axis and indicating no protuberance.

Figure 3 is a bottom view of the rifle shown in Figure l and cut away to indicate the detent position of the safety for snap action movement from safe and fire positions.

Figure 4 is a section taken on the line IV-IV of Figure 3 and showing the camming action against the sear block to lock the block against the falling of the sear.

Figure 4a is a view as indicated in Figure 4, but indicating the block unlocked by the selected cam position.

Figure 5 is a side elevation indicating the positioning of the block with respect to the spring loading of the block to urge the block counterclockwise on its pivot.

Figure 6 is an exploded view showing the parts of the safety and their interrelationship in the safety assembly.

Figure 7 is a schematic diagram showing the pivotal linkage between extreme block positions and indicating the engagement of the sear.

General description to the slide shaft of the safety. Resilient means, such as a spring, acting on the block, urges the base of the block into register with the cam surfaces of the slide shaft. A button flanging outwardly from one end of the safety is located at one end of the shaft, while the opposite end of the shaft selectively is extensible and retractable depending upon the button position. The plunger is unique- 1y secured against accidental loss as will be seen as the description proceeds. On one extreme of shaft travel one of the cam faces on the shaft rocks the block forward to block the sear. On the other extreme of travel the shaft center positions a deeper cam face which allows retraction of the block from sear engagement, in response to the bias of the resilient means. The entire safety assembly is located ina portion of the trigger guard as shown, and extends transversely therethrough. No unusual inletting is required and no positive reliance is placed on springs 'for'maintaining the safe position of manner. The safe position is positive in its prevention of the sear from dropping.

Specific description In Figure 1 the illustrated rifle 11 is' of the bolt action type. The bolt'12 extends from the breech portion nested in the ways. As the bolt 12 is rotated and drawn rearwardly for extraction of a spent cartridge, the bolt 12' is cocked andthe firing pin is positioned to compress-a spring in-'the bolt 12 and the cocking lug (not shown) of the bolt '-12 is positioned for release. When the bolt 12 'is closed-'and' a new'cartridge is inserted in the chamber portion 13, the firearm is cocked and the bolt 12 is locked as shown in the bolt slot 14. Thecocking lu'gis positioned and held by the sear 15 as the bolt 12 is rotated. The scar 15 is'pivotal on hearing pin 16. The trigger arm 17 extends 'upward to pivotally connect to the sear 15 by means of trigger pivot 18. The trigger arm 17 isp'rovided with a rearward extension 19 in substantial contact with the receiver group base 20. As the trigger 21 is drawn rearwardly in the trigger housing 22, the sear 15 is pivoted counterclockwise by reference to the drawing (Figure 1) in response to the levering action'of the trigger arm extension 19 acting on the trigger pivot 18. This causes the sear 15 to drop from its'en'ga'gement with the cocking lug and the firing pin is released inthe bolt 12 to fire the arm.

To provide control over the accidental discharge of the weapon a non-rotating cross shaft or plunger 23 is passed through a mating out of round opening 24 provided in the 'trigger'housing rear enlargement 25, adjacent the rear merger of trigger housing 22 and receiver group 26, as viewed in Figure 1. Thus, the shaft 23 is transversely positioned in respect to the axis of the bolt 12 and is beneath the bolt 12.

One end of the cross shaft 23 is radially flanged to form a button 27. The cylindrical form of the shaft 23 is upset by two cam surfaces, 28 and 30, the former being deeper than the latter. The deep face 28 is centered when the button 27 is flush against the trigger housing 22. As will be seen the rifle 11 may now be fired. In this position the small end 29 of the shaft 23 protrudes from the trigger housing 22"on the side opposite the button 27. When the small end 29 of the plunger 23 is pressed, the button 27 pops outwardly from the housing 22 in response to the axial movement of the shaft 23. This action centers the shallower 30 of the cam faces, between the'cheeks of the trigger housing 22 (Figures 4 and 4a).

Higher and forward of the location of the shaft 23 (in respect of Figure 1) a scar block pivot 31 is extended transversely through the housing 22 in a position concealed; by the stock. The pivot 31 parallels the shaft or plunger 23. The block 32 is journalled on the pivot 31. The base of the block 32 extends rearwardly'in the form of a dog 33 extending to engage the shaft'23 'in the position of its selected centered cam surfaces 28 and 30. A recess 34 is provided in the forward portion of the base of the sear block32 to accommodate a compression spring 35 and detent guide 35a which bears against a shoulder 36in the housing 22 to bias the block 32 in a counterclockwise movement (with respect to Figures 1 and 5) about the pivot 31 urging engagement of the dog'33 with selected'ca'm faces 28 or '30. The arm 37 of the block 32extends upward and radially from the pivot 31 (Figure 7). When rocked full forward on the pivot 31, compressing the spring 35, the arm 37 of the bl'o'ck32 is positioned directly beneath the sear 15 preventingthe sear 15 from falling and therefore preventing the-disehargeof"the firearm 11. "At the urging of'the spring 35 the block 32 rocks rearwardly on its pivot 31 as the shaft 23 is movedonits axis to center thedeep'er cam face 28 (Fignire 4a) and the sear 15 can fall to discharge the firearm 11 when the trigger 21 is pulled.

Positive control over the locking movement of the block 32 is accomplished by axially moving the shaft 23 in the housing 22 until the shallower 30 of the cam surfaces engage the dog 33 (Figure 4). The block 32 cannot move out from under the sear 15 until the button 27 centers the deep face 28 allowing the dog 33 of the block to drop as biased aboutthe pivot 31 by the spring 35.

Detent means 39 and 40 locatably secure the shaft 23 and prevent axial dislodgement of the shaft 23. The dentent means comprise a spring loaded plunger 39 and spring 40, the plunger 39 falls into recesses 41 and 42 in the shaft 23. The preferred position of the detent positioning means is in the bore 24 acting on the base of the plunger 23 Figures 1' and 3).

These positioning recesses 41 and 42' provide snap centering position control" for the cam surfaces 28 and30.

In adapting the unit above described to various makes of rifle it has been found universally desirableto remove a section from the button 27 leaving an upper'flat 43 so that the button 27 cleanly clears the stock. In other regards the arms 37 of the block 32 is ground to rock smoothly under the particular sear 15. By providing an annular groove 44, in the protruding small endof the shaft 23 and baking red enamel into the groove 44, visual means are easily provided which 'warn the riflernan that the safety is in firing position. In accord with good gunsmithing practice 'it will be appreciatedthat left and right hand installations can be'provided without a departure from the spirit of the present invention. Similarly the relative positions for location of the safety may be altered to adapt the safety to any particular arm 11.

Operation In the operation of the described safety device for bolt action rifles the plunger 23 is reciprocable in a direction transverse of the axis of the bolt 12. A concealed pivot 31 ahead and above the plunger 23 carries a scar block 32 having a cam follower dog extension33 which is urged by the spring loading of the block 32 to ride on the plunger or shaft 23. The plunger or shaft 23, being provided with a shallow 30 and deep cam face 28.,controls the rocking movement of theblock--32 about its pivot 31. In thecase of block engagement with the shallow cam face 'the block 32 is roc'ked forward and under the sear 15 of the rifle 11 preventing its discharge. When the plunger 23 is pushed to its other extreme of travel the deeper cam face 28 permits the spring urged block 32 to rock out from underthe sear 15 thereby allowing discharge of the firearm. The plunger or shaft 23 is secured against dislodgement by detent means and againstrotation by shoulder means at the one extreme of travel and by the button end27 on the other extreme of travel. Thus, upon assembly, when the dog extension 33 of the sear block 32 is spring pivoted into contact with the cam faces, the shoulder 45 on'the plunger 23 will not permit removal 'of the plunger 23 from the opening 24' until the block 32 is removed. Full depression of the block 32 on the spring 35 brings the spring loaded block 32 against the stop of the trigger housing base so that the dog 33 cannot clear the shoulder 45. Snap action centering of the cam surfaces 28 and 30is accomplished by thedetent action.

When the device of the present inventionhas been used on various bolt action military arms the conversion from military to sporting arms hasbeen=fast and entirely satisfactory. ,The safety-is comfortably. lo-

\ cated and avoids movement by accident. The safety installation requires nocxpensive inletting of the stock or'w'eakening ofessen-tial metal parts. The'device has been extensively used in field testing with excellent acceptance by sportsmen and hunters. In general, the safety of the present invention may be applied to all arms wherein the sear drops. In shotguns, for example, where the breech block carries the sear, simple relocation of the described structure adapts the described safety to block the sear until the block is released. Similarly, the form of the block can be altered to suit particular installations and reduce the overall weight of the arm.

Having thus described my invention it will be appreciated that modifications within the skill of the art are intended to be included limited only by the scope of the hereinafter appended claims.

I claim:

1. In a cross sear block type of safety for firearms, the combination including: a reciprocable plunger shaft having one deep and one shallow cam face therein; a pivot ahead of and above said plunger shaft and paralleling said shaft; a sear block pivotal on said pivot and resiliently biased to engage said shaft in contact with said cam faces on said shaft and rock on said pivot in accord with thc selected positions of said cam faces.

2. In a cross bolt sear block type of safety for bolt action rifles the combination including: a reciprocable plunger shaft transversely through the trigger guard of a bolt action rifle, said shaft being provided with one deep cam face and one shallower cam face; a pivot ahead of and parallel to said shaft and transversely through the trigger housing group of said rifle; a scar block pivotal on said pivot and provided with a rear dog extension engaging the selected cam faces on said shaft; said sear block being urged under the sear of said rifle by one position of said shaft and out from under the sear of said rifle by the other position of said shaft; resilient means biasing said sear block into engagement with said shaft; and means snap positioning said shaft in its selected positions.

3. In a safety for a bolt action rifle having a dropping gear, the combination comprising: a plunger adapted to extend transversely through the trigger housing of said rifle and having two selected cam faces, one of which is deeper than the other, only one of which faces is centerable at a given time; a rockable sear block member having a follower extension engaging the selected cam face at center on said plunger; resilient means urging said block into following contact with said cam faces so that when the deeper of said faces engages said block the sear of said rifle is free to fall, and when the shallower of said faces is engaged the said sear of said rifle is prevented from dropping; detent means acting on said plunger so that said cam faces are centered selectively by snap action; and securing means integral with said plunger, cooperating with said sear block preventing loss of said plunger from accidental dislodgement.

4. In a safety particularly adapted to bolt action arms having a dropping sear, the combination comprising: an out of round plunger adapted to extend transversely and reciprocably through the trigger housing of a rifle and having two selected cam faces, one of which faces is deeper than the other, only one of which faces is centered at a given time; a shoulder provided on one end of said plunger; a button flanging radially from said plunger at one end; a pivotal sear block having a rearwardly extending dog and an elongate arm, the said dog in following engagement with the selected of said cam surfaces on said plunger, the deeper of said faces allowing said block to pivot toward said plunger and the shallower of said faces pivoting said block away from said plunger; a pivot on which said sear block rides; said pivot being axially parallel to said plunger and offset therefrom by a distance sufficient to permit the dog of said sear block to engage said cam surfaces; spring means biasing said block into engagement with said plunger, and detent means engaging said plunger to snap action center said cam faces for engagement with said dog of said sear block.

No references cited. 

